You can't. All you can do is paint.
If the Thermofoil is cracked or peeling removing the plastic and painting is the only solution.
Thank you. I bet it’s difficult to remove all of it?
You can use a blow dryer to warm it up and soften the glue. Then just peel it off. If they are not that bad. You patch small cracks and cut out any small loose pieces. Use Bondo (auto body filler) to patch. Sand smooth. Then you can prime and paint. Use an acrylic latex paint since the plastic does expand and contract. Good temporary fix. Can't say how long it will last.